Take a Look. How Much Gas Do I have?

My SWMBO would love to answer that question.

Seriously. Do me a favor please and click here to see a pic of my regulator I just installed on my CO2 tank.

I don't know how to read these things. Can someone tell me how much gas they think I have in this tank. Its' a steel 20lb'r that I picked up and I don't know if it's full, empty or right in between.

NOTE - Click on the thumbnails to enlarge and maximize your browser to enlarge again...

I don't know how much you have, but generally if I'm "above the red" I feel okay. It also depends on the temperature of your tank...if it's cold it will read much lower than if it's warm.

It's not full, but I am told the nature of regulators seem to be that you will only notice a large difference towards the last 1/5 of the tanks life. This tank could be anywhere from 3/4 full to 1/4 in my opinion.

To echo the Baron, temp is a huge factor in the readings. At 60 degrees my tank reads 800, at 40 degrees it reads 500.

Put the thing on your bathroom scale. There should be a tare weight stamped on there someplace, so you know the weight of the container. Put it on the scale & do the math!

Bernie Brewer said:

Put the thing on your bathroom scale. There should be a tare weight stamped on there someplace, so you know the weight of the container. Put it on the scale & do the math!

Click to expand...

BRILLIANT !

Okay...TW# was 30lb
Weighed in at 54lb (including the Micromatic regulator...I'm guessing those things weigh about 3lbs?)

KalvinEddie said:

BRILLIANT !

Okay...TW# was 30lb
Weighed in at 54lb (including the Micromatic regulator...I'm guessing those things weigh about 3lbs?)

Click to expand...

OK that would put your CO2 at 21#. Since it's a 20# tank your scale or your estimate of the regulator might be off a bit, but I'd say the tank is pretty darned full.

So THAT is what the poundage rating of the tank means. I never thought it to be that simple. THANKS!

Your Gage is reading about where mine reads when I've just had it filled.
Remember, if you stick the tank in the fridge the gage will read low.

Yup! CO2 is sold by weight because the pressure is driven by temperature. Unless you keep it in a freezer, when it hits red it means all the remaining CO2 is vaporized & you are just about empty. My experience (with 5 lb tanks) is you will not be able to force carbonate a cornie at that point, although you can dispense two or three.

David's correct. The only way to determine how much you have is to weigh the tank. Compressed CO2 exists in a liquid/vapor state. Compressed CO2 also has a direct temperature/pressure relationship. The pressure in the tank will remain the same, at a given temperature, until all of the liquid has been vaporized. Once only vapor exists, the pressure in the tank will drop rapidly as you continue to serve.

Lower the temp of the tank, and the pressure drops. Raise the temp of the tank and the pressure rises. That is why you want to keep the tank away from heat sources, as it can over pressurize and blow the relief. That will wake you up!

Here is a pressure/temperature chart for CO2 that shows the relationship.

BTW, same principle goes for propane tanks............

This tank was too big to fit into a fridge... take a look here.

You can see where I mounted on the outside of my Sanyo 4912.